Autoimmune diseases are diseases arising from aberrant response of the immune system against one's own substances and tissues. There are more than 80 different types of autoimmune diseases that, collectively, amount to the number two cause of chronic illness, and one of the top 10 leading causes of death in women of all age groups up to 64 years.
Significant medical research efforts have been devoted to understanding the mechanism of autoimmune diseases and finding effective diagnosis and treatments therefore. Many autoimmune diseases are now characterized by the presence and undesirable activities of autoantibodies. These autoantibodies recognize and bind to often normal and healthy self antigens, thereby causing significant damages and failures of relevant tissues and organs.
Immune thrombocytopenia is an autoimmune hematological disease that is characterized by an attack by the immune system that destroys platelets in the blood, resulting in an abnormally low platelet count. The platelet destruction is due to the presence of antiplatelet autoantibodies, which are antibodies directed against the patient's own platelets. This low platelet count can lead to easy bruising, bleeding gums or nose and, less commonly, to severe internal bleeding.
Thrombosis is the formation of a blood clot in a blood vessel, which may obstruct blood flow in the blood vessel and consequently severely interfere with the function of the cardiovascular system. It is believed that thrombosis is associated with abnormal activation and aggregation of platelets.
Antiphospholipid syndrome (APS) is characterized by the presence of antiphospholipid (aPL) antibodies, in particular, antibodies against cardiolipin and beta2 glycoproteins. APS can cause thrombosis in both arteries and veins as well as miscarriage and maternal and fetal morbidity. Two forms of APS have been described: primary antiphospholipid syndrome (PAPS) (Asherson, R. A., et al., (1989) Medicine 68: 366-374), wherein no evidence of any underlying disease is found, and secondary antiphospholipid syndrome (SAPS) (Alarcon-Segovia, D. et al., (1989) Medicine 68: 353-365), wherein APS is associated with other diseases such as systemic lupus erythematosus (SLE).